The number of children classed as living in relative poverty is 2.3 million, the lowest level since the 1980s, according to figures published by the Government.

The Department for Work and Pensions said the percentage of children in relative low-income households remained "flat" in 2013/14.

There had been speculation that the figure, published annually, would increase to 2.5 million, while a row has been brewing over whether the Government is planning to change the way the figure is measured.

The current definition of child poverty is whether a child lives in a household with an income less than 60% of the national average.

Work and Pensions Secretary Iain Duncan Smith said: "These statistics show that the proportion of individuals with low income is now at the lowest level since the mid-1980s.

"We know that work is the best route out of poverty, with children in workless families around three times as likely to be in poverty than those in working families. That is why, as part of our long-term economic plan, our reforms to the welfare system are focused on making work pay, while our reforms to the tax system are allowing people to keep more of what they earn.

"Latest figures show UK employment has reached an all-time high, with employment up more than two million since 2010, and the number of households where no one works is the lowest since records began."

Labour MP Frank Field, who chairs the Work and Pensions Select Committee, said: " Politicians might understand these measurements but the electorate certainly doesn't. What I hope would interest the electorate is action to prevent poor children becoming poor adults.

"We must therefore begin talking about, and measuring, poor children's life chances and how they can be improved. It is important that such measurements are accurate, but that they can also safely drive anti-poverty policy."

The DWP said that in 2013/14, the average real terms household income before housing costs (BHC) remained unchanged from 2012/13 at £453 a week.

Average household income after housing costs was also unchanged at £386, said the department.

The percentage of children in relative low income BHC remained flat at 17%, its lowest level since 1980s, said the DWP.

The figures saw a general decrease between 2007/8 and 2010/11 and have remained broadly stable to 2013/14, the department added.

Javed Khan, chief executive of children's charity Barnardo's, said: "Every child living in poverty is a child that's being let down. Child poverty is a direct reflection of a failure, as a society, to protect our most vulnerable families.

"Poverty is blighting the life chances of our children, making them more likely to fall sick, do less well at school and be unemployed in the future. Government plans to cut struggling families' incomes further by changing tax credits is deeply concerning.

"So that every child gets the chances in life every child deserves, this Government must ensure that change to the benefits system makes work pay for those on low incomes, and doesn't force families further into poverty."

TUC general secretary Frances O'Grady said: "Despite the headline employment rate returning to its pre-recession level, absolute poverty rates are still higher. Our economy is not creating enough good quality jobs to achieve the larger falls in poverty we need to give every worker a decent life and every child a decent future.

"The extreme cuts to tax credits the Government is planning for working families will do nothing to raise wages and will leave low-paid families even worse off. There's a big danger this will start poverty rates rising again."

David Simmonds, chairman of the Local Government Association's Children and Young People Board, said: "Councils are working hard to help tackle child poverty through their successful economic development strategies and by directly working with families in difficulty.

"Regardless of how statistics are compiled, we recognise that there are parts of the UK where there is much more to be done to raise children out of poverty and councils are playing an extremely active role because their detailed knowledge of their local community means they are best placed to lead the way."

Matthew Reed, chief executive of the Children's Society, said: "It is a scandal that there are 200,000 more children who have been pushed deeper into poverty over the past year, as today's figures reveal.

"There has also been a steady rise over the last five years in the numbers of children living in in-work poverty, clearly showing that even those families with jobs are suffering because of Government policies.

"Moving the goalposts by changing the definition of child poverty will do nothing to help the millions of children who are suffering in real poverty. The Government needs to stop debating definitions and start doing more to help children."

Campbell Robb, chief executive of Shelter, said: " It's shocking to see hard evidence of families starting to sink rather than swim, as they deal with the double blow of welfare cuts and sky high housing costs. And sadly behind each of these statistics lies the story of a parent desperately struggling to keep their family's heads above water.

"This Government has the opportunity to be the first in generations to turn things around so children aren't the ones paying the price for our housing crisis. The only way to do this is by rethinking further cuts that will push even more families over the edge, and building the genuinely affordable homes we so desperately need."

Gingerbread chief executive Fiona Weir said: "Today's child poverty statistics show that children in working single parent families simply cannot afford to bear a cut to tax credits, with one in four already growing up poor.

"Two in five of the UK's three million children in single parent families are below the poverty line, and work is not offering these families a guaranteed route out of poverty."

Alison Garnham, chief executive of the Child Poverty Action Group, said: "These figures make grim reading for anyone looking for progress on child poverty. Because, make no mistake, we are facing a child poverty crisis in the years ahead and the Government is not going to meet the child poverty targets it signed up to.

"Rather than opening up opportunity, the UK is now going down the road of closing down life chances for hundreds of thousands of children in low-income families.

"On the Government's preferred absolute poverty measure, there are half a million more children in poverty than there were in 2010.

"This child poverty crisis will undoubtedly deepen if the Government goes ahead with plans to cut help for children in low-income families and for the low paid. You don't tackle low pay by making the low paid poorer. You don't tackle child poverty by slashing targeted help for children in low-income families and then claiming money doesn't matter."

Chris Leslie, shadow chancellor, said: "These statistics show a depressing lack of progress we should be making as a country towards the abolition of child poverty in the UK.

"The Government needs a serious strategy to address low pay and boost productivity, rather than 'redefining' the child poverty statistics and pretending the problem has just gone away.

"A plan to reduce child poverty is needed now, rather than threats to cut £5 billion from tax credits which would mean 3.7 million working families losing, on average, £1,400 a year. That will not address child poverty - it will add to it.

"Ministers should now take responsibility and tackle low pay, not attack the low paid."

Prime Minister David Cameron's official spokeswoman said: "What today's statistics show is that the proportion of individuals in poverty is at the lowest level since the mid-1980s.

"The Prime Minister... remains committed to doing more work to eliminate child poverty and that is precisely why the Government wants to look at having an approach that is focused more on tackling the root causes of poverty than treating the symptoms."